aafvstam

Although the foundation is on Windows Server 2003 the product is nothing like the server. Your granny can work with it, it has a simplified interface (console) where you can manage your home pc's to backup and store all of your digital assets with the option
to duplicate the files on the same server for safety reasons. (if one breaks you always have the other to your avail).

The hardware reqs are not even that high, there are Atom editions with only 2Gb but personally I like it to have a little more power. But if you have a spare low end machine that might be sufficient to work on.